mobile stack view stopped being a fallback

the mobile stack view is now its own screen instead of a redirect to list view.

it shows every stack tag from the tracker snapshot, then lets you tap into the projects and updates using that stack. the first version was too simplified. it looked cleaner, but it hid real data. this version is messier in the right way: complete, browseable, and tied to the actual tracker.

we also fixed “other builds.” those entries now act like individual project cards on mobile, so clicking a stack tag only shows work that actually uses that stack.